Work for the coming year will deal, for the most part, with (a) relating changes in the biological activity of lipoteichoic acid from a group B streptococcal clinical isolate with changes in its lipid moiety using human cell lines in tissue culture as the assay system, (b) quantitatively comparing the types and amounts of teichoic acid being excreted by Streptococcus pyogenes, a group B streptococcus and their respective L-forms and determining at what stage of growth this excretion becomes most pronounced for each of these organisms and (c) determining if collagen synthesis in animal cells is directly affected by streptococcal lipoteichoic acid and, if so, whether this occurs before any morphological change becomes apparent in such cells.